and this is the final time barack obama will ever do this. this is his last political campaign and the last rally and so tonight this cold iowa air is thick with emotion and nostalgia and edged with a bit of anxiety about what will happen tomorrow. you talk to the obama people, they express kind of gritty, grim, even, confidence. they think they'll get it done. but they know this time so different from the last time. it's not about inspiration, it's about perspiration, all about hard work. madison, wisconsin this morning, bright and crisp and obama crowd filling the streets about 18,000 of them. sort of fired up. sort of ready to go. >> i don't know. it's pretty early to be fired up. >> reporter: bruce springsteen came and sang. ♪ no retreat >> reporter: and this time around for obama and his crowd the gritty courage, mournful determination in his song rings truer, perhaps. >> incredible crowd and it's good to be back. >> reporter: he has changed so much. he's in the fight of his life and he knows it and his hoarse voice told the tale. >> w